Internal combustion engines are used in a variety of applications, such as for lawn mowers and snow blowers. Such engines often have carburetors wherein fuel received from a fuel source is mixed with air and supplied to a combustion chamber for ignition.
To aid in starting such engines it is desirable to introduce a small amount of fuel directly into the carburetor or fuel intake system. This may be accomplished through the use of a priming device, many of which have been marketed or illustrated in the patent literature. One such type of priming device includes a primer bulb that when depressed, displaces a volume of air into a carburetor float bowl or fuel well wherein the pressurized air pushes fuel from the carburetor into the engine intake system.
Bulb priming devices are typically located on the engine housing. The operator of a device such as a lawn mower or snow blower, standing upright behind the handle, is required to crouch down near the engine to prime the engine. Therefore, it would be desirable if the operator could prime the engine remotely from his upright position.
Bulb priming devices for internal combustion engines are well known in the prior art. U.S. Pat. No. 3,345,045 to Tuggle discloses a primer for an internal combustion engine, that uses a primer bulb, located on the engine, to pressurize air whereby fuel is injected into a fuel intake system. A primer bulb of this type could be located remotely from the engine but requires running air tubes from the bulb to the engine. Such tubes can easily be damaged if located on or near a handle section. Further, a remote primer of this sort requires a larger bulb than one located near the engine. The larger bulb is necessitated by substantial pressure losses that are increased with greater tubal lengths.
To provide convenience, remote switching devices have been designed for use on a variety of devices. For instance, a remote switching mechanism is disclosed in U.S. Pat. No. 5,023,417 to Magiera. This mechanism uses a bowden cable with a manually actuable member on a first end and a ball or spring on a second end that engages an electrical rocker switch. The '417 device does not disclose a remote switch that automatically returns to its unactuated state after it has been actuated, which is desirable when using the remote device to depress a primer bulb.